This invention relates to barrier devices for vehicular and vessel traffic control, soil erosion containment, impact attenuation and the like which can be interconnected with one another to define a continuous barrier wall structure and/or connected in various combinations to form energy-absorbing cells, and, more particularly, to barrier devices formed of a light weight plastic having openings extending through the hollow interior of the barrier which receive and mount external reinforcement structure in the form of a pair of beams each extending along the length of one of the side walls and are connected to one another through the openings.
A variety of different devices have been developed for absorbing the kinetic energy of impact of colliding automobiles, and for the containment of forces exerted by soil or water. Highway barrier devices, for example, are intended to provide a continuous wall or barrier along the center line of a highway when laid end-to-end to absorb grazing blows from moving vehicles. One commonly used highway barrier is formed of pre-cast reinforced concrete, and is known as the xe2x80x9cNew Jerseyxe2x80x9d style barrier. Highway barriers of this type have a relatively wide base including side walls which extend vertically upwardly from the pavement a short distance, then angle inwardly and upwardly to a vertically extending top portion connected to the top wall of the barrier. This design is intended to contact and redirect the wheels of a vehicle in a direction toward the lane of traffic in which the vehicle was originally traveling, instead of the lane of opposing traffic. See U.S. Pat. No. 4,059,362.
One problem with highway barriers of the type described above is the high weight of reinforced concrete. A barrier having a typical length of twelve feet weighs about 2,800-3,200 pounds and requires special equipment to load, unload and handle on site. It has been estimated that for some road repairs, up to 40 percent of the total cost is expended on acquiring, delivering and handling concrete barriers. Additionally, concrete barriers have little or no ability to absorb shock upon impact, and have a high friction factor. This increases the damage to vehicles which collide with such barriers, and can lead to serious injuries to passengers of the vehicle.
In an effort to reduce weight, facilitate handling and shipment, and provide improved absorption of impact forces, highway barriers have been designed which are formed of a hollow plastic container filled with water, sand or other ballast material such as disclosed in U.S. Pat. Nos. 4,681,302; 4,773,629; 4,846,306, 5,123,773 and 5,882,140. For example, the ""302 patent discloses a barrier comprising a container having a top wall, a bottom wall, opposed side walls and opposed end walls interconnected to form a hollow interior which is filled with water, and having fittings for coupling one barrier to another to form a continuous wall. The container structure is formed of a resilient material which is deformable upon impact and capable of resuming its original shape after being struck. Longitudinally extending, spaced traction spoiler channels are said to reduce the area of potential impact and thus the tendency of the vehicle to climb the walls of the barrier and vault over it into the opposing lane of traffic.
The ""629, ""306, ""773 and ""140 patents noted above were invented by the present inventor and represent further advances in deformable highway barrier designs. The first two patents disclose barriers which comprise a longitudinally extending container made of semi-rigid plastic which is self-supporting, and has a predetermined shape which is maintained when filled with water, sand or other ballast material. Such devices are connected end-to-end by a key insertable within grooves formed in the end walls of adjacent barriers. Interconnected fill openings are provided which permit adjacent barriers to be filled with water or the like when laid end-to-end.
The ""773 and ""140 patents disclose further improvements in barrier devices including side walls formed with higher curb reveals, a horizontally extending step and vertical indentations in order to assist in maintaining the structural integrity of the container, and to create internal baffles for dampening movement of water or other fluid within the container interior. Interlocking male and female coupling elements are formed on opposite end walls of the barrier to facilitate end-to-end connection thereof. Additionally, such barriers are formed with channels or openings to permit the insertion of the tines of a fork lift truck therein for easy handling of the barriers.
Despite the improvements in highway barrier designs noted above, some deficiencies nevertheless remain. One concern has been with the ability of a wall of barriers, e.g. individual barriers connected end-to-end, to withstand a direct impact by a speeding vehicle. It has been found that plastic barriers tend to separate from one another at their connections, and in some instances break apart in response to the vehicle impact. Although concrete barriers of the type described above also can break apart during a crash, they are more resistant to that than plastic barriers and there is a need for plastic barriers to demonstrate impact resistance capabilities which more closely approximates those of concrete barriers.
It is therefore among the objectives of this invention to provide a barrier device for use as a highway barrier or other energy absorbing structure which is easily transported, handled and assembled, but which is also resistant to being broken apart in response to an impact with a vehicle.
These objectives are accomplished in a barrier device comprising a top wall, a bottom wall, opposed end walls, and, opposed side walls interconnected to form a hollow interior in which a pair of spaced openings are formed which extend between the side walls. An external reinforcement structure is provided to enhance the structural integrity of the barrier device, including first and second beams each extending along one of the side walls which are connected to one another by a mounting device extending through the openings, or, alternatively, are mounted within a seat formed in each side wall between the opposed ends of the barrier device. The beams of one barrier device, in turn, are connected end-to-end with the beams of an adjacent barrier device to form an essentially continuous, interconnected wall of barriers which resist disengagement from one another and exhibit improved resistance to being broken apart upon impact by a vehicle.
The openings extending through the hollow interior are fork lift holes which are sized to receive the tines of a fork lift to permit movement of the barrier device during loading, unloading and assembly. In one presently preferred embodiment of this invention, the external reinforcement structure comprises a first box beam and a second box beam, each generally square in cross section and formed of metal, rubber, composite material or the like. Each box beam is hollow, at least at its opposite ends, in order to receive and mount one end of a connector bar whose other end is mounted within the box beam of an adjacent barrier device. The cross section of the connector bar is sufficiently smaller than that of the box beams to permit at least limited pivotal movement of the connector bar within the beams, and hence, pivotal movement between the adjacent barrier devices.
The two box beams are connected to one another by a pair of brackets each including a plate mounted at each edge to one of a pair of upstanding legs. One bracket is inserted within each of the fork lift holes and has a length dimension such that its ends protrude from the side walls. Each box beam rests atop a protruding end of both brackets and is bolted in place to connect it to the bracket and, in turn, to the box beam on the other side wall. Because the brackets have upstanding legs, clearance is provided within each fork lift hole to receive the tines of a fork lift even with the brackets and box beams in place.
In an alternative embodiment, a pair of box beams similar to those noted above are employed except they are connected to one another by telescoping members associated with each beam. One of the box beams mounts a pair of sleeves extending perpendicular thereto, and the other box beam mounts a pair of arms which align with the sleeves and are inserted therein when the beams are positioned along the side walls. The box beams associated with one barrier device are connected to those of an adjacent barrier by means of telescoping ends of the beams. One end of each beam has a reduced cross sectional area which telescopes into the opposite end of an adjacent beam having a larger cross section. The beams of one barrier device may be connected to the beams of an adjacent barrier device by a friction fit, or with fasteners such as bolts.
Additional embodiments of this invention employ xe2x80x9cbeamsxe2x80x9d in the form of the box beams noted above, or solid slats, which are mounted within longitudinally extending seats formed in the side walls of each barrier device between the end walls. These seats receive and frictionally maintain the beams in place, and connecting structure is provided to mount the ends of each beam of one barrier device to those of an adjacent barrier device.
In another aspect of this invention, a rotational molding process is employed to combine crosslinkable high density polyethylene material with polyethylene foaming pellets to form the barrier device noted above with walls having an interior surface covered with a layer of foam. The plastic, polyethylene walls have a thickness on the order of about 0.25 inches, and the foam layer is in the range of about 0.5 to 6 inches in thickness depending upon the amount of foaming pellets used. Fill holes are formed in the top wall of the barrier so that water, sand or other ballast material can be introduced into the hollow interior and into contact with the foam layer. In an alternative embodiment, substantially the entire hollow interior of the barrier is filled with foam material. Preferably, a liquid material is introduced into the hollow interior through one or more of the fill holes, which then cures to form a foam which expands to fill all or a part of the entire volume of the barrier interior.
It has been found that barrier devices filled with foam can be interconnected end-to-end to form a barrier wall which readily floats in water, and the external reinforcement structure adds overall strength, rigidity and resistance to separation and breaking apart of individual barriers within such barrier wall. These floating barrier walls can be used in various naval applications to encircle ships or other assets, or to segregate areas within a port or dock area, as desired.